touchscreen "tracing" problem & weird bar on topSupport

HELP! Had my HTC 4g for 3 months. Yesterday for now reason a tiny bar appears at the top of all screens with numbers next to pg:, dx:, dv:, xx:, etc. Looks like coordinates.
At the same time anytime i touch the screen a blue tracer line appears where my finger slide across the screen. Does not matter where I am or what application I'm in. Anyway to clear this ? thank you

I wonder if something happened (is continuing to happen) at Verizon. My daughter had this exact thing happen to her cellphone on Thursday, 12/6. She texted me in a panic because her phone had a "messed up" screen with the "p: dx: dy: xv: prs: size" message and a "blue cross that draws blue where my finger touches". I did some research on the internet and found out, as other posters have noted, that it had to do with some options in Developer Options/User Interface being checked. Told my daughter to go to that screen and see if any of the options had been checked. Turns out that 4 items were indeed checked, and by unchecking them the "messed up" screen was completely fixed. Got a huge "Thank You" from my daughter - which was a rare and very appreciated treat, haha. Now here's the weird thing - her cellphone is a Motorola Droid 4 (on the Verizon network, of course) and this screen issue happened while her phone was safely tucked away in her pocket during school class. So she had a perfectly fine phone walking into class and when she emerged from class and took her phone off sleep in order to use it, the "messed up" screen popped up. All in all, such a strange thing to happen, but happily it was easily and quickly fixed.